Distillation of petroleum oils



May 2, A A MacCUBB|N Er AL DISTILLATION OF PETROLEUM OILS Filed Dec. l5, 1928 I adv-LMI* ATTORNEYS Summa auf #Fati Patented May 2, 1933 UNITED STATES PATENT OFFICE ALEXANDER A. IACCUBBU, 0F MONTG'LAIB, AND JOSEP# ZAVERTNIK, JB., OF HAB- BIN'GTON PABX, 'NEW JERSEY, ASSIGNOBS, BY MESNE ASSIGNMENTS, T0 WARREN 'W'. GRIMM, 0F NACOGIDOCHES, TEXAS DIBTILLATION 0F PETROLEUM OILS -Application led December 15, 192B. Serial No; 326,175.

This invention relates to improvements in the distillation f of petroleum, and includes improvements in both method and apparatus. More particularly the invention relates to improvements in the distillation of petroleum in which pipe stills are employed and in which -the heat su plied to the petroleum in the pipe still is su equently employed to obtain additional distillation in a particularly advantageous way.

In the operation of pipe coil stills for the distillation of petroleum the residual oil produced as a result of the distillation is usually drawn oi at a high temperature as a finished product and is employed as fuel oil, or is permitted to cool and solidify when of semi-solid or solid consistency, or is passed to other stills in which it is subjected to further distillation for the production of additional oil and of a heavier residue lor coke therefrom. When pipe stills are employed for sim le distillation, as distinguished from crac ing, there is a limit to the extent to which the distillation can be carried because, if the petroleum is heated to too high temperatures, some of the oil is cracked or decomposed, particularly thel heavy viscous products, the paraiiine wax and other products, with the result that there is a decrease in valuable oil yields of heavy oils and a decrease in the viscosity of the roducts. If the oil is kept at a sufiicient y low temperature to avoid cracking or decomposition of the petroleum and its residuals the oil yields are limited and the` extent to which the distillation can` be carried limited.

The present invention enables high oil the pipe coil still.I .This further distillation,

under a vacuum, is accomplished without heating the residual oil to a higher temperature, and where no additional heat is supplied to the residual oil the distillation is accomplished with lowering of the temperature of the residual oil, so that the high grade residual oil withdrawn from the vacuum still will be at a lower temperature than that withdrawn from the pipe coil still.

According to the present invention the oil, which may be a crude oil or a topped or partially distilled oil is subjected to distillation in a pipe still by pumping the oil continuously through a pipe coil and heating it therein and discharging it therefrom into a vapor chamber Where the va ors are separated from the unvaporized resi ue; and.

the unvaporized residue is then Withdrawn to a vacuum still Where it is subjected to a high vacuum, and where the residual heat contained in the residue is employed for accomplishing further distillation and the production of an additional amount of distillate of high boiling point. In the present process the vacuum is not applied directl to the vapor chamber of the pipe coil stil b.ut ,is applied to the hot residual oil roduced by the pipe coil still after this resi ual oil has been withdrawn from the vapor chamber of such still. The vapors separated in the vapor chamber of the pipe coil still are passed to the condenser without being subjected to a vacuum. The application of a vacuum to the vapor chamber of the pipe coil still would add to the diiliculty of condensing the distillate and would result in the expansion of a large amount of light oil vapors. In the ypresent process, however, the vacuum is ap lied only to the residue from the pipeV coll still, after it has been freed from vapors in the vapor chamber, so that the high vacuum causes the distillation of heavy oil contained in the residue, which heavy oil vapors can be readily condensed by cooling under a high vacuum.

In carrying out the present process it is to further increase the distillation.

ofadvantage to use the petroleum first as a condensing medium for the vapors produced by the distillation, thereby preheating the petroleum at the same time that the distillate vapors are cooled. rlhis preheating is accomplished in the condensers and heat interchanger through which the oil is pumped under pressure and in indirect heat interchanging relation with the vapors. By regulation of the process, the petroleum can be preheated in this Way to a temperature suflicient to distill off some o'f the lighter oils, such as the gasoline and naphtha fractions, by discharging the preheated oil into a vapor box or chamber where the light vapors are separated and from which they are withdrawn to a condenser.

The crude oil thus preheated and freed from part of its light oils is then subjected to distillation in a pipe coil still in which it is pumped through a pipe coil under pressure and heated therein to a high temperature and in which the pipe coil discharges into a vapor box or chamber Where the oil vapors are separated from the residual unvaporized oil and from which the oil vapors are withdrawn to a condenser.

The petroleum residue is drawn ofl' from the vapor chamber of the pipe coil still and is passed continuously to a vacuum box or still where it undergoes further distillation with its self-contained heat and Where an additional amount of the heavy oil is distilled therefrom and a heavier residue produced.

The pipe coil still em 'loyed may be a single sta e still or a mu ti-stage still, that is, a singe pipe coil with a single vapor chamber, or successive pipe coils and vapor chambers in which the petroleum oil is heated to progressively higher'temperatures, with the taking o' of progressively higher boiling fractions from the successive vapor chambers, and with the production of progressive'- ly heavier residual oils, the residual oil from lone vapor chamber being the oil charged to the next pipe coil except in the case of the last vapor chamber from which the residual oil is passed to the vacuum still.

The vacuum box or still into which the residue from the pipe coil still is continuously introduced need not be independently heated, although additional heat may be supprllileld e original heat contained in the hot residue is su ient to effect a further distillation of additional oil from the residue when it is subjected to a high vacuum in the vacuum still. The present process thus makes use of the large amount of sensible heat contained in the residue dischar d from the vapor chamber or vaporizer o the pipe coil still to distill an additional amount of hea' 'y oil from the residue by reduction of pressure on this residue while it is still ata high temperature and after it has been produced in and separately withdrawn from the pipe coil sti l.

The present rocess also includes improvements in the su sequent treatment of the residues produced in the vacuum still, where additional distillation thereof and the production of Va still heavier residue or of coke is desired. The residue from the vacuum still may be a high grade flux oil, if asphaltic base petroleum is used, or it may be a heavy cylinder stock if parafline base petroleum is used, and such oils may be used as iinished products or may be further treated. The flux residue from asphaltic base petroleums may be passed to separate stills and there blown with air to produce asphalt. The paraiine base residue can be used in making heavy cylinder stock by subjecting it to special treatment or it can be further distilled by passing it as a thin film over molten metal in a still maintained under a high vacuum Where it undergoes further distillation with heat supplied by the molten metal and Where `additional c linder oil stock is distilled therefrom and co e produced.

The improved apparatus of the present invention includes a pipe coil still and a vacuum still so connected that the hot residue from the pipe coil still passes directly to the vacuum still. The apparatus also includes condensers and heat interchangers in which the petroleum is preheated under pressure and in which the preheated oil is discharged into a vapor box or separating chamber where the light oil vapors are separated from the petroleum, and from which the topped oil iiows to the pipe coil still. The pipe coil still may be a single stage or multistage pi e coil still in which the petroleum is heate to a high temperature under pressure and discharged therefrom into a vapor box or separating chamber where the vapors are separated from the petroleum residue. The vacuum box or still is so arranged that the hot oil residue from the pipe coil still is drawn continuously into the vacuum still and there maintained under a high vacuum so that further distillation is effected by the reduction in pressure, While the residue is still at a sufficiently high temperature to 1 enable such distillation to take place on reduction of pressure.

Where the residue from the vacuum still is to be further treated, the apparatus includes an additional still or stills for such further treating or distillation, for example, a thin film still for further distilling and coking parailine base residues by passing them in a thin film over molten metal under a high vacuum; or, in the case of ashaltic residues, one or more oxidizing still 1n which the hot residue from the vacuum still is blown with air to oxidize the asphaltic flux and produce high grade asphalt there- 'from. The apparatus includes pressure and vacuum producin devices whereby pressure can be maintaine on the etroleum passing through the preheater an through t e pipe coils, and whereby a high vacuum can e maintained in the vacuum still. The vapor boxes are ordinarily maintained at atmospheric pressure or at a pressure approximating atmospheric. Where paraliine residues are further distilled to coke under a high vacuum suitable provision is made for maintaining a high vacuum on such still. The apparatus includes suitable condensers for condensing the distillate oils fraetionally to recover different oil fractions therefrom. It also includes heat interchangers to preheat the petroleum oil by heat interchange with the distillates.

The process and apparatus of the present invention enable a wide range of oil fractions to be produced and enable the dili'erent fractions to be regulated to obtain fractions suitable for various purposes without further re-fractionation. The process can be operated, for example, to produce as separate products gasoline, naphtha, kerosene, high or low test burnin oils, gas oil, wax distillate, lubricating oils o varying characteristics inl cluding oils of high .fire test, etc.

The present process and apparatus can be employed for the distillation of crude oil or of topped crude or of residual products produced by other preliminary processes of distillatiou. lVhere crude oil is used, it can advantageously be topped and simultaneously preheated by heat interchange with the oil vapors being condensed by forcin the crude oil under pressure through heat interchangers heated by the oil vapors and discharging| the preheated 'oil into a vapor separating chamber. The oil vapors will be' simultaneously cooled and condensed and their heat largely recovered in preheating the crude oil.

The temperature to which the petroleum or residual oil is heated in the pipe coil still can be somewhat varied but in general the temperature should not be sufficiently high to cause cracking or objectionable decomposition of the petroleum or residual oil passing,

through the still. However, b pumping the oil through the still at a rapi rate-it can be momentarily heated to a high tem erature immediately prior to its discharge om the heating coil without any appreciable cracking taking place. The temperature to which the. oil can be heated without appreciable cracking will vary somewhat with dilerent oils and residues, but the `process and apparatus can be so operated that the residue produced in and withdrawn from the vapor chamber of the still= may have a temperature approaching the cracking temperature.

The residue leaving the pipe coil still and entering the vacuum still may have a tem-v perature, for example, of around 60G-700 F.

or higher. On enterin the vacuum still in which a high vacuum 1s maintained it will undergo furthe: distillation with resulting oil content of the hot residual oil will be` distilled which would not be distilled at the same temperature under atmospheric pressure. i

The distillation of petroleum in a pi e coil still followed by subsequent distillation of the separated residue in a vacuum still has the advantage that the petroleum can be rapidly and continuously distilled by rapidly and continuously pumping it through the pipe coil and heating it therein to a high temperature without maintaining the etroleum at a h'igh temperature for more t an a very short period of time, thus minimizing danger of cracking or decomposition of the oil. The petroleum heated to a high temperature in the pipe coil still and immediately discharged into the vapor chamber of the still will be somewhat cooled by the vaporization which takes place in the vapor chamber from which the vapors are drawn oil` and condensed. The residue from the vapor chamber will, however, be at a sufficiently high temperature so that when flashed by .sudden reduction of pressure on entering the high'vacuum still, a considerable .further distillation will take place. The maximum temperature to which the petroleum or residual oil is heated is that in the pipe coils and by regulating and limiting this temperature and the period of time to which the petroleum or residual oil is subjected to it, objectionable decomposition of oil constituents can be largely avoided, thus giving an increased yield of .valuable high boiling constituents.

The invention will be further described in connection with the accompanying drawing which is of a conventional or diagrammatic character and in the nature of a flow sheet and which shows arrangements of apparatus embodying the invention and adapted for the ,y ractice of the process of the invention, but itis intended and will be understood that the invention is not limited thereto. I

In the accom anying drawing, the crude petroleum or ot er petroleum oil to be distilled is supplied from storage tank 1 and is pumped by pum 2 to the fractionating condenser 3 in whic it is brought into indirect contact-and heat interchan ng relation with hot oiL vapors and therelgy17 preheated. It Vthen passes through heat interchangers 4 and 5 in indirect contact with hot condensates from the condensers 6 and 7, serving to cool these condensates while the crude oil itself is further preheated. It then passes through fractionating condensers 6 and 7 Where it is brought into indirect contact and heat interchanging relation with hot oil vapors and Where it is further preheated. The crude oil is pumped through these preheaters and heater interchangers under pressure and is then discharged to a vapor box or vaporizer 8 maintained at or approximately at atmospheric pressure. In this vaporizer 8 light oil vapors, such as those of gasoline or naphtha, are separated and passed to the fractionating condenser 3V where they serve to preheat the cold crude oil. The gasoline and naphtha fractions condensed in the condenser 3 flow by gravity to their respective oil receivers.

The crude oil thus preheated and freed from its light oil fractions is pumped from the vaporizer 8 by means of pump 9 through the pipe coil heater 10 where it is heated to a high temperature and then discharged into the vapor box or separator 11 where the oil vapors are liberated and separation of unvaporized oil residue takes place. The oil is pumped through the pipe coil under pressure, but the vapor chamber 11 is maintained at or approximately at atmospheric pressure although at times it may have a pressure somewhat above or somewhat below atmospheric. In general, however. the pressure in the vapor separating chambers 8 and 11 does not vary materially from atmospheric pressure. The vapors set free and separating in the vapor chamber 11 pass to the iractionating condenser 7 where theyr are condensed and from which separate oil fractions are withdrawn, each to its own receiver. Among the fractions which may be thus collected are heavy naphtha, refined oil, gas oil` light wax distillate, etc. The oil vapors in the condenser serve to preheat the crude oil in the manner above described.

Instead of withdrawing the residual oil from the vapor chamber 11 to a storage tanl; or to separate stills for its further distillation by the further application of heat, in accordance with processes heretofore proposed, this residual oil is drawn oil from the bottom of the vaporizer through a line 13 having a pressure regulating valve 12 therein into a vacuum box or still 14.

The vapor separating chamber 11 will be at approximately atmospheric pressure while the vacuum still 14 will be under a high pressure, around 27 to 29.9 inches vacuum. The vacuum still will ordinarily be placed at an elevation above the vapor chamber 11 so that the residue will be drawn through the line 13 bv the vacuum maintained in the vacuum still. In case the elevation of the still 14 is not suilicient to maintain the desired vacuum,

a further regulation of pressure can be maintained by the valve 12 so that reduction in pressure Will-take place at the valve 12 and in the line 13 as the residue passes upwardly therethrough from the valve 12 to the vacuum still 14. Reduction of pressure at the valve 12 will result in som'e vaporization of oil constituents of the residue, and this vapor-ization will increase as the residue is drawn up through the line 13, and the distillation under a high vacuum will be completed in the still 14 to the extent that the heat contained in the residue is suiiicient to accomplish distillation under the high vacuum maintained. The sensible heat contained in the residual oil supplies heat sufficient for the latent heat of vaporization of a considerable part of the oil content of the residue, and this vaporization is substantially instantaneous due to reduction of pressure. As a. result, thc resid-ue is almost instantly cooled by the vaporization thus reducingr it to a temperature such that further cracking is practically eliminated, even though the residue may have been heated to the cracking temperature at the time of discharge from the pipe coil heater.

The vapors of heavy oils set free in the vacuum still pass through the condensels where they are condensed and where they serve to preheat the crude oil. The vacuum is maintained in the vacuum still by the vacuum pump 19 shown as a three stage ejector pump. inasmuch the oil is separated from moet or all of its low boiling constituents in the vapor chambers 8 and 11, the distillate formed in the vacuum still 14 will be a heavy distillate which can be readily condensed even under a high vacuum during its passage through the condenser ti.

The heavy residue remaining in the vacuum still can be Withdrawn as a inished product. or it can be subjected to further treatment. By supplying the vacuum still with additional heating means (not shown) additional distillation can be accomplished there- `n and a still heavier residue and an increased yield of heavy distillate produced. In its broader aspect, the invention is not limited to any subsequent treatment of the residue from the vacuum distillation. but includes a process in which the residual oil from the continuous or intermittent stills is withdrawn while still at a high temperature. Without material cooling, to a vacuum still maintained at a high vacuum where the latent heat required for the vaporization of part of the residue is obtained from the sensible heat contained in the residual oil together with additional heat if necessary from an outside source. When additional heat is supplied it may advantageouslybe in the form of heating surfaces or elements over which the residual oil is caused to flow in thin films in the vacuum still.

Where the residue from the vacuum distillation is to be further treated or distilled, theV f present invention provides for such further treatment or distillation. In the case of resi dues from paraiine base petroleum oil, such residues can be directly treated by refining agents to produce lubricating oil stocks, or they can be subjected to further distillation by passing them to a coke still `maintained under a high vacuum where the paraiiine base petroleum will be distilled to coke and a heavy paraifine lubricant will be obtained, to-

ether with some admixed product resulting from the destructive distillation involved in the coking operation. Different types of coke stills can be employed. One form of still involves maintaining a molten metal bath in the still and introducing the residue from the vacuum still in the form of a thin film over the surface of the molten metal so that the residue will be distilled to produce a coke residue. The vapors from this vacuum coke still, indicated at 15, will pass to the fractionating condenser 17 from which the oil fractions will pass to oil receivers. The vacnum coke still can be maintained at a vacuum of 27 to 29.7 inches by a suitable vacuum box shown as a three stage ejector pump, 18. The condensers will be maintained at the same vacuum as the still itself but the heavy distillates will readily condense even under a high vacuum. The oil receivers may be at atmospheric pressureand located at a suflicient distance below the condensers so that they flow by gravity through a` barometric discharge pipe without breaking the vacuum in the condenser. Any uncondensed gas is discharged from the vacuum system by the vacuum pump 18, When the vacuum coke still 15 is operated with a body of molten metal therein. the film of coke continuously formed may be scraped o and discharged into one or other of two discharge receptacles 16, either of which can be disconnected. VSuitable scrapers (not shown) may be provided for scraping `the thin layer of coke from the surface of the molten metal into the discharge to the coke receptacle. Y

When ux oil is produced as a residue from asphalt base crude oil, this flux oil may flow by gravity from the vacuum still 14 through a barometric column 21. By providing a barometric column in which there is maintained a column of oil sufficient to overcome the high vacuum maintained, the flux oil will How by gravity to the stills 20. These stills 20 are oxidizing stills provided with means (not shown) for blowing air through the flux oil to produce asphalt of high grade therefrom. High melting point asphalt flux oils canf thus be produced having a melting pointup to around 110 F. (A. S. T. M. Method D- 36-26) or higher. Such flux oils are moreover obtained at the same time that a high yield of distillate oils can be obtained, and

they are subjected to the oxidation treatment.

Some of the residues produced by the resent process, and also some of the disti ates produced, may be of a solid or semi-solid character when cold. In order to avoid solidiication of high melting point residues or of the heaviest of the distillates, it is important to provide suitable insulation for the parts of the a paratus through which the oils and residua oil are passed so as to permit withdrawal thereof from the a paratus in a liquid and thinly lluid state. imilarly with the condensers employed for condensing the heaviest distillate, which may be of a thick viscous or semi-solid consistency when cold, it is important to maintain the condensers hot, or at such a tem rature that the condensates will flow there rom in a liquid and thinly Huid state.

It is also important to avoid heat loss in the operation of the apparatus, to provide suitable insulation for the lines and apparatus containing the hot oils and residues, and particularly the residues from the pipe coil still to the vacuum still. By means of suitable insulation, and the avoidance of unnecessary heat losses, the high temperature and heat content of the hot residues from the pi e coil still can be effectively employed for dlstillation of a considerable amount of additional heavy oil from the residue on reduction of pressure from atmospheric to a high vacuum, even where no added heat is supplied. In such case, the further distillation by ilashin under vacuum is obtained entirely by the sel contained heat of the hot residual oil from the pipe coil still, which is made available by the reduction in pressure from atmospheric to the high vacuum. In order to obtain maximum distillation, additional heat may be supplied to the vacuum still to supplement that contained in the hot residue.

rllhe arrangement of the various oondensers is such that fractional condensation of the vapors can be eiected, and each condenser is provided with a final coolin section in which cooling water is employed. he arran ment is such that a greater or less part of t e con, denser can be employed for preheating the crude oil and simultaneously coolin and con-- densing oil vapors, and for comp eting the cooling and condensation by cold water. The condenser 17 is provided with only` a. water cooler, but the temperature and rate of supply of the water should be regulated with reference to the heavy distillate produced so that the distillate on cooling Will flow from the condenser in a iiquid and thinly fluid condition.

It will be seen that the present process and apparatus provides for applying a vacuum in a vacuum still to the residue produced i by the prior distillation, Without applying the vacuum to the vapor separating chamber of the prior distillation still. The vapors are taken off from the preliminary distillation stage of the process at practically atmospheric pressure, and are condensed at that pressure, and only the residue from this prior distillation is drawn off separately and subjected to a high vacuum to accomplish further distillation of it and the production of a heavy distillate which can be readily condensed even under a high vacuum. This residual oil will have been freed from a large part of its normal oil content before it is subjected to the vacuum distillation so that it will contain only or mostly high boiling oils. A high vacuum can be much more readily maintained Where only the hot residual oil is subjected to the vacuum than Where the vacuum is supplied directly to the entire vapor production of the pipe coil still in the vapor box of that still. Moreover, the condensation of the heavy distillate from the separated residue can be more readily accomplished under a high vacuum than the condensation of the entire vapor production of the pipe coil still. The high vacuum can be readily maintained by a suitable vacuum pump and by discharging from the vacuum still and from its condensers the residue and condensate through barometric columns containing heads of liquids greater than that corresponding to the vacuum maintained.

The present process enables a Wide range of fractions to be directly produced from petroleum oils. The lightest fractions, such as gasoline and naphtha, can be obtained from the preheating stage of the process, before the oil enters the pipe coil still The distillate produced in the pipe coil still includes medium and some of the heavy oils, such as kerosene, gas oil, paraffine oil, etc.,.vvhile the distillate from the vacuum still includes still heavier distillates such as heavy lubricating oiis, ctc. When the residue from the vacuum stiil is subjected to further distillation in a high vacuum coke still` additional heavy distillates can be obtained suitable for lubricating or other purposes.

It will thus be seen that the present invention provides an improved method and apparatus for distilling petroleum in a continuous manner and with notable heat economy, as Well as with the production ot a high grade asphalt or lubricating stock and a high oil yield. It will further be seen that the distillation is accomplished Without overheating or cracking of the petroleum or residual oil and that the maximum temperature to which the petroleum or residual oil is heated in the pipe coil still is not exceeded in the further distillation of the residual oil, but this further distillation is accomplished with lowering ot temperature or with the avoidance of further objectionable decomposition or cracking.

We claim:

1. The method of distilling petroleum which comprises subjecting petroleum to distillation in a continuous manner by passing it through a pipe coil and heating it therein to a temperature sufficient to vaporize considerable proportions of the oil contained in the petroleum, discharging the resulting product into a vapor separating chamber at approximately atmospheric pressure with resulting production and separation of oil vapors and a residual oil, drawing off the residual oil through a pressure reducing and regulating valve to a vacuum box or still While it is still at a high temperature and thereby effecting further distillation of the oils from the residual oil` the flow of residual oil from the pipe coil still to the vacuum still being accomplished by the vacuum maintained in the vacuum still and being regulated by the pressure regulating valve.

2. The method of distilling petroleum which comprises first subjecting petroleum to distillation by heating it in a pipe coil to a temperature sufficient to vaporize consid-` erable proportions of the oil contained in the petroleum. and discharging the resulting product into a vapor separating chamber at substantially atmospheric pressure to produce distillate oils and residual oil, withdrawing the residual oil during distillation while it is still at approximately the temperature of the first distillation and immediately subjecting it to a high vacuum to effeet further distillation of high boiling point oils therefrom by the self-contained heat of the hot residual oil, and passing the residue vfrom such distillation to a coke still maintained under a high vacuum and distilling the same to coke by the addition of heat and condensing the distillate under a high vacnum.

3. The method of distilling petroleum and of producing distillate oils and coke therefrom in a continuous manner, which comprises heating the petroleum-in a pipe coil to a temperature suiicient to vaporlze considerable proportions of the oil contained in the petroleum, discharging the heated product into a vapor separating chamber at approximately atmospheric pressure, subjecting the residue to a high vacuum to effect distillation of additional oils therefrom thereby distilling oils and producing a residual oil, withdrawing the residual oil during distillation While it is still at practically its maximum temperature and allowing it to How into a vessel containing molten lead, thereby removing lubrieating oils and producing'coke in a continuous manner.

4. That improvement in methods of distilling petroleum which comprises subjecting the petroleum to distillation continuously by passing it through a pipe coil and heating it therein to a temperature suiiiciently high to vaporize portions of the lighter .oils contained in the petroleum, discharging the heated petroleum into a vapor separating chamber maintained at approximately at mospheric pressure with the resulting production of distillate light oils and a residual oil, drawing oil' the residual oil through a pressure reducing and regulating valve to a vacuum still and in said vacuum still subjecting the heated residue to a high vacuum to eil'ect vaporization of a complex distillate containing the higher boiling point oils and thereafter separately collecting and con: densing the distillate evolved by the vaporization under vacuum.

5. That improvement in methods of eX- tracting oils of intermediate boiling point from a complex hydrocarbon mixture containing the same, which comprises subjecting a heated and continuously flowing stream of the mixture to the following steps in the sequence named: First, removing at substantially atmosphericy pressure the low boiling point oils contained in the continuously flowing mixture: second, withdrawing through a pressure reducing and regulating valve the continuos- 'uving mixture from which the lower lfoilf4 third, plaire; under f single high vacuum the mixture flowing continuously from the pressure reducing and regulating valve to effeet complete and simultaneous vaporization of the intermediate boiling point oils; fourth, eliminating from the continuously flowing mixture those heavy and impure matters not vaporized under vacuum; and, fifth, fractionally condensing the vaporized oils according to their boiling points. A

In testimony whereof we 4atlix our signatures.

ALEXANDER A. MAGCUBBIN. JOSEPH ZAVERTNIK, JR.4

point oils have been extracted ;4

DISGLAIM ER 1,907,328.Alexander A. MacUubbimMontclair, and Joseph Zavertmlk, Jr., Harrington Park, N. DISTILLATION 0F PETRoLEUM OILS. Patent dated May 2, 33. Dlselanner filed December 29, 1937, by the assignee, l/Varren W.

mm. p Hereb enters his disclaimer to claim 5 of said Letters Patent.

Gazette Jamlary 25, 1.938.]

taining molten lead, thereby removing lubrieating oils and producing'coke in a continuous manner.

4. That improvement in methods of distilling petroleum which comprises subjecting the petroleum to distillation continuously by passing it through a pipe coil and heating it therein to a temperature suiiiciently high to vaporize portions of the lighter .oils contained in the petroleum, discharging the heated petroleum into a vapor separating chamber maintained at approximately at mospheric pressure with the resulting production of distillate light oils and a residual oil, drawing off the residual oil through a pressure reducing and regulating valve to a vacuum still and in said vacuum still subjecting the heated residue to a high vacuum to eil'ect vaporization of a complex distillate containing the higher boiling point oils and thereafter separately collecting and con: densing the distillate evolved by the vaporization under vacuum.

5. That improvement in methods of eX- tracting oils of intermediate boiling point from a complex hydrocarbon mixture containing the same, which comprises subjecting a heated and continuously flowing stream of the mixture to the following steps in the sequence named: First, removing at substani tially atmosphericy pressure the low boiling point oils contained in the continuously flowing mixture: second, withdrawing through a pressure reducing and regulating valve the continuos- 'uving mixture from which the lower holf l point oils have been extracted ;4 third, piero; under f single high vacuum the mixture flowing continuously from the pressure reducing and regulating valve to effeet complete and simultaneous vaporization of the intermediate boiling point oils; fourth, eliminating from the continuously flowing mixture those heavy and impure matters not vaporized under vacuum; and, fifth, fractionally condensing the vaporized oils acleording to their boiling points. A

In testimony whereof we 4affix our signa- 5 JOSEPH ZAVERTNIK, .im

DISGLAIM ER 1,907,328.Alexander A. MacUubbimMontclair, and Joseph Zavertmlk, Jr., Harrington Park, N. DISTILLATION 0F PETRoLEUM OILS. Patent dated May 2, 33. Dlselanner filed December 29, 1937, by the assignee, l/Varren W.

mm. p Hereb enters his disclaimer to claim 5 of said Letters Patent.

Gazette Jamlary 25, 1.938.] 

